膝关节软骨退行性变的声像学表现

目的 探讨膝关节软骨不同时期退行性变（退变）的声像学表现，并设立相应的超声诊断标准。 方法 对行关节镜手术的9个膝关节用超声术中经皮实时观察，对关节置换术的2个膝关节标本（置生理盐水中）进行离体观察。 总结 正常膝关节软骨及软骨Ⅰ～Ⅳ期退变的超声表现。 结果 正常膝关节软骨表现为高-低-高“夹心饼断面”样回声带。膝关节软骨Ⅰ期退变通常改变很不明显。Ⅰ期退变软骨表面毛糙，轻度变薄或局部隆起。Ⅲ期退变软骨局部明显变薄。Ⅳ期退变软骨完全缺失。 结论 膝关节软骨除Ⅰ期退变外，其余各期关节软骨退变在超声上均有特定表现。     

超声、MRI评价不同分期膝关节软骨退行性变的比较

目的比较超声、MRI评价不同分期膝关节软骨退行性变与手术分期的相关性。方法选择40例患者41个拟行关节镜手术或关节置换术的膝关节,术前采用超声观察股骨内髁、股骨外髁、股骨滑车正中沟、滑车内侧斜面和滑车外侧斜面,共计205个关节面。其中11个膝关节接受了MRI检查。评价2种影像学手段判断膝关节软骨退变的分期与手术分期的相关性。结果超声、MRI评判软骨退变的分期与手术分期的相关系数分别为0.703（P〈0.05）、0.778（P〈0.05）。结论超声、MRI评判膝关节软骨退变的分期与手术分期均有较好的相关性,能反映出病变的严重程度,有助于估计病情、指导治疗。     

超声评估膝关节软骨退行性变的应用价值

目的：采用高频超声探查拟行关节镜手术及关节置换术的膝关节，评估超声对软骨退行性变的诊断效能。方法：选择2004-02／08在中山大学第三附属医院行膝关节镜手术患者36例37个膝关节及关节置换术患者4例4个膝关节。男13例，女27例，年龄8-75岁，病程1个月～20年。分别对每个膝关节的5个关节面，共计205个关节面的软骨进行高频超声探查，并将超声表现与关节镜结果及手术切除标本对照。结果：40例41个膝关节，均进入结果分析。超声诊断膝关节软骨退行性变的敏感性、特异性、准确性分别为64．9％，92．0％，76．5％。膝关节软骨退行性变超声表现为软骨表面毛糙、变薄或消失、局部隆起，回声改变和软骨下骨质改变等征象。结论：超声评估膝关节软骨退行性变具有一定的敏感性和较高的特异性．可作为诊断膝关节软骨退行性变的重要筛查手段。     

超声评价不同分期的膝关节软骨退行性变

目的探讨超声诊断膝关节软骨退行性变分期的临床价值。方法超声探查40例患者的41个拟行关节镜手术或关节置换术膝关节，均观察其股骨内髁、股骨外髁、股骨滑车正中沟、滑车内侧斜面和滑车外侧斜面，共计205个关节面。超声结果与手术所见对照。结果超声诊断膝关节软骨退行性变（退变）的敏感性、特异性、准确性分别为64．9％、92．0％、76．5％。但对Ⅰ、Ⅱ期的诊断敏感性（46．7％）远远低于Ⅲ、Ⅳ期（75．7％）。结论超声评价膝关节软骨退变具有一定的敏感性和较高的特异性，可作为诊断该病的重要筛查手段。     

超声评估膝关节软骨退行性变的应用价值

目的:采用高频超声探查拟行关节镜手术及关节置换术的膝关节,评估超声对软骨退行性变的诊断效能。方法:选择2004-02/08在中山大学第三附属医院行膝关节镜手术患者36例37个膝关节及关节置换术患者4例4个膝关节。男13例,女27例,年龄8～75岁,病程1个月～20年。分别对每个膝关节的5个关节面,共计205个关节面的软骨进行高频超声探查,并将超声表现与关节镜结果及手术切除标本对照。结果:40例41个膝关节,均进入结果分析。超声诊断膝关节软骨退行性变的敏感性、特异性、准确性分别为64.9%,92.0%,76.5%。膝关节软骨退行性变超声表现为软骨表面毛糙、变薄或消失、局部隆起,回声改变和软骨下骨质改变等征象。结论:超声评估膝关节软骨退行性变具有一定的敏感性和较高的特异性,可作为诊断膝关节软骨退行性变的重要筛查手段。     

肌骨超声及MRI对膝关节退行性骨关节炎的诊断价值

目的  评估肌骨超声及MRI对膝关节退行性骨关节炎（KOA）的诊断价值。方法  选择2017年1月~2019年12月在我院接受治疗并全部接受关节镜检查的单侧KOA患者126例为研究对象。对所有纳入研究的患者行超声检查、MRI检查及关节镜检查,对肌骨超声图像及MRI图像行质量评价。以关节镜检查结果为金标准,分别评估超声、MRI检查对关节积液、滑膜增生、髌上囊积液、关节软骨损害、骨质增生、半月板损伤、韧带损伤等病变的诊断价值。结果  126例患者成功接受肌骨超声、MRI及关节镜检查。以关节镜结果为金标准,超声检查及MRI检查在KOA患者滑膜增生、髌上囊积液、半月板损害、韧带损伤、肌腱断裂及腘窝囊肿的检出中与关节镜结果一致性好（超声Kappa值：0.81、0.85、0.79、0.79、1.00、1.00,MRI Kappa值：0.76、0.93、0.86、0.89、1.00、1.00,Kappa值均 > 0.75）;在KOA滑膜增生和骨质增生的诊断中,超声检查的诊断效能好于MRI检查（AUC=0.978、0.972,P < 0.05）;在关节积液、髌上囊积液、关节软骨损害、韧带损伤的诊断中,MRI检查的诊断效能好于超声检查（AUC=0.991、0.995、0.969、0.961,P < 0.05）;在韧带损伤的诊断中,超声检查与MRI检查的诊断效能差异无统计学意义（P > 0.05）;126例患者中,超声检查认为有57例患者存在关节间隙狭窄,平均关节间隙为3.54±0.53 mm,MRI检查认为有52例患者存在关节间隙狭窄,平均关节间隙为3.62±0.61 mm,两者测量差值无统计学意义（P > 0.05）。结论  肌骨超声及MRI检查能较好的识别膝关节退行性骨关节炎病变特征,具有较高的临床运用价值。     

超声、X-线平片和MR对膝关节软骨退行性变诊断价值的比较

目的比较超声、X-线平片和MR评价膝关节软骨退行性变（退变）的优劣。 方法选择40例患者41个拟行关节镜手术或关节置换术的膝关节，术前采用超声和X-线平片观察股骨内髁、股骨外髁、股骨滑车正中沟、滑车内侧斜面和滑车外侧斜面，共计205个关节面。其中11个膝关节接受了MR检查，以关节镜或置换术标本所见为对照，比较3种影像学手段对软骨退变的诊断水平。 结果超声、X-线平片和MR诊断膝关节软骨退变的敏感性、特异性、准确性分别为：超声64．9％、92．0％、76．5％；X-线平片46．3％、75．0％、58．5％；MR79．4％、86．2％、82．5％。超声诊断敏感性、准确性低于MR，明显高于X-线平片，而特异性高于MR。 结论超声对膝关节软骨退变的诊断水平低于MR，明显高于X-线平片，可以作为初查手段推广应用。     

膝关节软骨退变的高频超声诊断价值

目的探讨高频超声对膝关节软骨退变的诊断价值。方法选择拟行膝关节镜手术的病人100例,术前1周行超声检查,观察股骨内髁、股骨外髁、滑车正中沟及其内侧斜面、外侧斜面共500个关节面,以关节镜检查结果为金标准行对照研究,分析高频超声诊断膝关节软骨退变的灵敏度、特异度、准确度,以及超声与关节镜评价软骨退变的一致性。结果超声诊断膝关节软骨退变的灵敏度为74.9%,特异度为78.6%,准确度为76.3%;超声与关节镜分期结果的一致性属中度（K=0.46,P〈0.01）。结论超声诊断膝关节软骨退变具有较高灵敏度、特异度及准确度,与关节镜分期有较好的一致性,可以作为临床诊断膝关节软骨退变的重要辅助手段。     

基层医院超声诊断误诊漏诊的相关因素分析

目的:超声诊断已是临床及医学影像必不可少的学科之一,其诊断准确率是其它医学影像不可替代的,但同时我们也看到超声诊断仍然存在部分的误诊、漏诊现象,主要表现在超声仪器的因素、超声医师技术水平因素、工作量大而繁重、患者期望值过高、超声诊断医疗风险规避等方面。     

常规膝关节磁共振成像对退行性骨关节病的诊断价值及准确性分析

目的:探讨针对退行性骨关节病变实施常规膝关节磁共振成像的诊断价值及准确性。方法:选取兰陵县人民医院2020年7月—2021年10月收治的疑似退行性骨关节病患者70例,均实施常规膝关节磁共振成像诊断、常规X线诊断,以关节镜手术结果为参考标准,对比两种方式阳性检出率、诊断效能以及对不同病变情况的检出结果,分析影像学特征。结果:70例疑似退行性骨关节病患者中,关节镜检查结果证实有69例为退行性骨关节病患者。常规膝关节磁共振成像阳性检出率90.00%高于常规X线诊断的84.29%;常规膝关节磁共振成像诊断准确度、敏感度、特异度、阳性预测值及阴性预测值均高于常规X线诊断,但差异无统计学意义(P>0.05)。常规膝关节磁共振成像检查软组织肿胀、半月板变性、骨质增生、关节面不平、关节积液、滑膜增厚、软骨下囊变的检出率均高于常规X线检查,差异具有统计学意义(P<0.05)。结论:退行性骨关节病变的临床诊断中实施常规膝关节磁共振成像具有较高诊断准确性,值得推广。     

超声对不同部位股骨关节面软骨退行性变的对比研究

目的探讨超声评价不同部位股骨关节面软骨退行性变的优劣。方法超声探查40例患者41个拟行关节镜手术或关节置换术的膝关节，均观察其股骨内髁、股骨外髁、股骨滑车正中沟、滑车内侧斜面和滑车外侧斜面，共计205个关节面。超声结果与手术所见对照。结果超声对滑车关节面病灶的诊断水平远远优于内、外髁，敏感性、特异性、准确性分别为：滑车中央沟76．9％、100％、92．5％；滑车内侧斜面96．0％、85．7％、91．3％；滑车外侧斜面65．2％、95．2％、79．5％；外髁54．5％、100％、70．6％；内髁50．0％、69．2％、54．7％。所有位于外髁负重面偏内侧和内髁负重面近髁间嵴的病灶，超声均未能显示。结论超声对股骨滑车软骨退行性变的诊断水平优于股骨髁，而外髁负重面偏内侧、内髁负重面偏髁间嵴区域是超声的扫查盲区。     

Ultrasound Evaluation of Site-Specific Effect of Simulated Microgravity on Articular Cartilage

Space flight induces acute changes in normal physiology in response to the microgravity environment. Articular cartilage is subjected to high loads under a ground reaction force on Earth. The objectives of this study were to investigate the site dependence of morphological and ultrasonic parameters of articular cartilage and to examine the site-specific responses of articular cartilage to simulated microgravity using ultrasound biomicroscopy (UBM). Six rats underwent tail suspension (simulated microgravity) for four weeks and six other rats were kept under normal Earth gravity as controls. Cartilage thickness, ultrasound roughness index (URI), integrated reflection coefficient (IRC) and integrated backscatter coefficient (IBC) of cartilage tissues, as well as histological degeneration were measured at the femoral head (FH), medial femoral condyle (MFC), lateral femoral condyle (LFC), patello-femoral groove (PFG) and patella (PAT). The results showed site dependence not significant in all UBM parameters except cartilage thickness (p < 0.01) in the control specimens. Only minor changes in articular cartilage were induced by 4-week tail suspension, although there were significant decreases in cartilage thickness at the MFC and PAT (p < 0.05) and a significant increase in URI at the PAT (p < 0.01). This study suggested that the 4-week simulated microgravity had only mild effects on femoral articular cartilage in the rat model. This information is useful for human spaceflight and clinical medicine in improving understanding of the effect of microgravity on articular cartilage. However, the effects of longer duration microgravity experience on articular cartilage need further investigation. (E-mail: rsguoxia@inet.polyu.edu.hk)     

Strain-Dependent Modulation of Ultrasound Speed in Articular Cartilage Under Dynamic Compression

Mechanical properties of articular cartilage may be determined by means of mechano-acoustic indentation, a clinically feasible technique for cartilage diagnostics. Unfortunately, ultrasound speed varies in articular cartilage during mechanical compression. This can cause significant errors to the measured mechanical parameters. In this study, the strain-dependent variation in ultrasound speed was investigated during dynamic compression. In addition, we estimated errors that were induced by the variation in ultrasound speed on the mechano-acoustically measured elastic properties of the tissue. Further, we validated a computational method to correct these errors. Bovine patellar cartilage samples (n = 7) were tested under unconfined compression. Strain-dependence of ultrasound speed was determined under different compressive strains using an identical strain-rate. In addition, the modulation of ultrasound speed was simulated using the transient compositional and structural changes derived from fibril-reinforced poroviscoelastic (FRPVE) model. Experimentally, instantaneous compressive strain modulated the ultrasound speed (p < 0.05) significantly. The decrease of ultrasound speed was found to change nonlinearly as a function of strain. Immediately after the ramp loading ultrasound speed was found to be changed –0.94%, –1.49%, –1.84%, –1.87%, –1.89% and –2.15% at the strains of 2.4%, 4.9%, 7.3%, 9.7%, 12.1% and 14.4%, respectively. The numerical simulation revealed that the compression-related decrease in ultrasound speed induces significant errors in the mechano-acoustically determined strain (39.7%) and dynamic modulus (72.1%) at small strains, e.g., at 2.4%. However, at higher strains, e.g., at 14.4%, the errors were smaller, i.e., 12.6% for strain and 14.5% for modulus. After the proposed computational correction, errors related to ultrasound speed were decreased. By using the correction, with e.g., 2.4% strain, errors in strain and modulus were decreased from 39.7% to 7.2% and from 72.1% to 35.3%, respectively. The FRPVE model, addressing the changes in fibril orientation and void ratio during compression, showed discrepancy of less than 1% between the predicted and measured ultrasound speed during the ramp compression. (E-mail: juha.toyras@kuh.fi)     

Ultrasound Biomicroscopy Imaging for Monitoring Progressive Trypsin Digestion and Inhibition in Articular Cartilage

This study reports an ultrasound biomicroscopy (UBM) imaging approach to monitor the progressive trypsin-induced depletion of proteoglycan (PG) and its inhibition in articular cartilage. Three fresh, normal bovine patellae were obtained and four full-thickness cartilage-bone specimens were prepared from the lower medial side of each patella. One sample was used as a control and the other three were divided into three groups: Groups A, B and C (n = 3 for each group). After a 40 min 0.25% trypsin digestion, samples from group A were continuously digested in trypsin solution, while those in groups B and C were immersed in physiologic saline and fetal bovine serum (FBS), respectively, for another 280 min. The trypsin penetration front was observed by UBM and M-mode images were acquired using 50 MHz focused ultrasound and custom-developed software. The results show that the 40 min trypsin digestion degraded nearly the whole surface layer of the cartilage tissue. Further digestion in trypsin or residual digestion in saline for 280 min depleted most of the PG content, as observed in groups A and B. The replacement of trypsin with a physiologic saline solution only slightly slowed the digestion process (group B), while trypsin inhibitors in FBS stopped the digestion in approximately 1.5 h (group C). The normalized digestion fractions of the digested tissues were calculated from ultrasound data and histology sections, and then compared between the groups. Without the use of FBS, 80% to 100% of the full thickness was digested, while this number was only approximately 50% when using FBS. Our findings indicate that the UBM imaging system could provide two-dimensional (2-D) visual information for monitoring progressive trypsin-induced PG depletion in articular cartilage. The system also potentially offers a useful tool for preparing cartilage degeneration models with precisely controlled PG depletion. (E-mail: ypzheng@ieee.org)     

Mitigation of Articular Cartilage Degeneration and Subchondral Bone Sclerosis in Osteoarthritis Progression Using Low-Intensity Ultrasound Stimulation

The purpose of this study was to evaluate the effect of low-intensity ultrasound on articular cartilage and subchondral bone alterations in joints under normal and functional disuse conditions during osteoarthritis (OA) progression. Total of thirty 5-mo-old female Sprague–Dawley rats were randomly assigned to six groups (n?=?5/group): age-matched group, OA group, OA?+?ultrasound (US) group, hindlimb suspension (HLS) group, HLS?+?OA group and HLS?+?OA?+?US group. The surgical anterior cruciate ligament was used to induce OA in the right knee joints. After 2 wk of OA induction, low-intensity ultrasound generated with a 3-MHz transducer with 20% pulse duty cycle and 30 mW/cm² acoustic intensity was delivered to the right knee joints for 20 min a day, 5 d a week for a total of 6 wk. Then, the right tibias were harvested for micro-computed tomography, histologic and mechanical analysis. Micro-computed tomography results indicated that the thickness and sulfated glycosaminoglycan content of cartilage decreased, but the thickness of the subchondral cortical bone plate and the formation of subchondral trabecular bone increased in the OA group under the normal joint use condition. Furthermore, histologic results revealed that chondrocyte density and arrangement in cartilage corrupted and the underlying subchondral bone increased during OA progression. These changes were accompanied by reductions in mechanical parameters in OA cartilage. However, fewer OA symptoms were observed in the HLS?+?OA group under the joint disuse condition. The cartilage degeneration and subchondral bone sclerosis were alleviated in the US treatment group, especially under normal joint use condition. In conclusion, low-intensity ultrasound could improve cartilage degeneration and subchondral sclerosis during OA progression. Also, it could provide a promising strategy for future clinical treatment for OA patients.     

Ultrasound Arthroscopy of Human Knee Cartilage and Subchondral Bone in Vivo

Arthroscopic ultrasound imaging enables quantitative evaluation of articular cartilage. However, the potential of this technique for evaluation of subchondral bone has not been investigated in vivo. In this study, we address this issue in clinical arthroscopy of the human knee (n = 11) by determining quantitative ultrasound (9 MHz) reflection and backscattering parameters for cartilage and subchondral bone. Furthermore, in each knee, seven anatomical sites were graded using the International Cartilage Repair Society (ICRS) system based on (i) conventional arthroscopy and (ii) ultrasound images acquired in arthroscopy with a miniature transducer. Ultrasound enabled visualization of articular cartilage and subchondral bone. ICRS grades based on ultrasound images were higher (p < 0.05) than those based on conventional arthroscopy. The higher ultrasound-based ICRS grades were expected as ultrasound reveals additional information on, for example, the relative depth of the lesion. In line with previous literature, ultrasound reflection and scattering in cartilage varied significantly (p < 0.05) along the ICRS scale. However, no significant correlation between ultrasound parameters and structure or density of subchondral bone could be demonstrated. To conclude, arthroscopic ultrasound imaging had a significant effect on clinical grading of cartilage, and it was found to provide quantitative information on cartilage. The lack of correlation between the ultrasound parameters and bone properties may be related to lesser bone change or excessive attenuation in overlying cartilage and insufficient power of the applied miniature transducer.     

An Ultrasound Biomicroscopic and Water Jet Ultrasound Indentation Method for Detecting the Degenerative Changes of Articular Cartilage in a Rabbit Model of Progressive Osteoarthritis

It is important to assess the early degeneration of articular cartilage associated with osteoarthritis (OA) for early intervention and treatment planning. Previously, we have developed a high frequency ultrasound and water jet indentation method for the morphologic, acoustic and mechanical assessment of articular cartilage, using the enzymatic digestion as a model of osteoarthritic degeneration. No naturally degenerated articular cartilage has been tested with the developed method. In this study, we aimed to determine the usefulness of the developed method for detecting the natural degeneration of articular cartilage in a standard surgical model of OA in rabbits. Forty adult New Zealand white female rabbits were used in this study, which included 30 experimental rabbits undergoing the right anterior cruciate ligament transection surgery and 10 control rabbits. At the 3^rd, 6^th, and 9^th week post-surgery, 10 experimental rabbits were sacrificed, respectively, for assessment of the knee cartilage quality. The cartilage at the medial and lateral femoral condyles and tibial plateaus (four points) was measured by the high frequency ultrasound biomicroscopy, the water jet ultrasound indentation and a contact mechanical indentation test before a histopathologic analysis for grading of degeneration severity. Measured parameters were compared among different groups classified either by post-surgery time or by histopathologic grade. The results showed a general trend of increase for ultrasound roughness index and a general trend of decrease for integrated reflection coefficient, stiffness coefficient from water-jet indentation and Young's modulus (E) from the mechanical indentation with the increase of post-surgery time. Comparisons among groups with different histopathologic grades showed similar trend with the increase of degeneration severity. The water jet ultrasound indentation method was demonstrated to be an effective method to measure the mechanical properties of the articular cartilage and with further development of arthroscopic ultrasound probe; it has the ability to assess the early degeneration of articular cartilage with measurement of morphologic, acoustic and mechanical properties of the cartilage in vivo.